Objective To study whether it can be directly compared that one of X ray pictures taken in different period and exposure conditions with one processed by histogramnormalization.
目的探讨不同时期、不同条件的X线片图像做直方图归一化处理后能否直接进行灰度或颜色的对比。
2
Some normalization methods are discussed in detail, including histogram method, expectation-variance method and trend surface analysis.